I have had the same problem with mine. I have a custom cat-back exhaust now with no mufflers that i run at the track and for shows. There is NO smell when i run this set-up because its straight through and the air has no muffler to twist through. I switch back to the factory set-up and it smells like rotten eggs again. My guess is that it has something to do with the muffler. I also get NO carbon build up on the tips with the no muffler set-up. If the no muffler set-up was quieter, i would run it all day long!!!!

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